Raceway element and method for its manufacture

ABSTRACT

A sheet metal strip configured for use as an inner or outer raceway of a rolling-element bearing, and a method of forming the raceway by punching and/or laser cutting a strip of material from a metal sheet, bending the sheet into a ring and welding the ends of the strip together, and mounting the strip on a circular inner or outer surface to form an outer or inner raceway.

CROSS-REFERENCE

This application claims priority to German patent application no. 102020 208 269.3 filed on Jul. 2, 2020, the contents of which are fullyincorporated herein by reference.

TECHNOLOGICAL FIELD

The present disclosure relates to a raceway element for a bearing, inparticular a raceway element of a rolling-element bearing, and to abearing including at least one such raceway element and a method formanufacturing such a raceway element.

BACKGROUND

From the prior art, raceways made from thin-walled metal are known forrolling-element bearings, which raceways are formed by rolling andsubsequent deep drawing. For this purpose a pot-shaped raceway blank isgenerated in possibly multiple deep-drawing steps. The pot-shapedraceway blank has a substantially cylindrical shape, including a collarthat is located on the side opposite the closed side of the pot. Thedeep drawing can be effected in a plurality of steps until the desiredheight is achieved for the later raceway. Subsequently a base of thepot-shaped raceway blank thus generated is cut out, and the collargenerated by the deep drawing is removed.

In order to provide the raceway thus obtained with necessary surfaceproperties, further processing steps, such as, for example, hardening,annealing, or other surface treatments may be required in order toobtain the desired material properties for the raceway.

Accordingly a series of machines as well as process steps are requiredfor the manufacturing of the raceway, with the result that, inparticular in the case of small quantities, the manufacturing isuneconomical.

SUMMARY

It is therefore an aspect of the present disclosure to provide a racewayelement that can be manufactured with reduced expense.

In the following a raceway element is disclosed for a bearing, inparticular a raceway element of a rolling-element bearing, wherein theraceway element is configured as an inner ring or as an outer ring, oris configured to be attachable to an element serving as inner ring or asouter ring for the bearing or to an inner ring or outer ring of thebearing. In order to reduce material and manufacturing costs, theraceway element is manufactured from a sheet metal panel. In particular,the sheet metal panel can already have a surface treatment required forthe finished raceway element. Alternatively the surface treatment canalso be effected on the manufactured raceway element and/or in anintermediate step of the manufacture.

Furthermore, the sheet metal panel can already have the thicknessdesired for the raceway element. In addition, not just a single racewayelement, but rather many raceway elements can be manufactured from themetal plate, which raceway elements can also differ in their dimensions.

The sheet metal panel is preferably manufactured from a metal that issuitable to provide the desired material properties for a raceway. Forthis purpose known steels can be used in particular, such as, forexample, strip steel, construction steel, case hardened steel, ortempered steel. The steel used can preferably be suitable to be weldedin order to make possible, for example, a material-bonded connectionbetween two parts. However, other types of connections, such as, forexample, an interference-fit connection or a friction-fit connection,can also be used. In particular, the sheet metal panel can already beheat treated and/or surface treated. The sheet metal panel preferablyhas a thickness between 0.5 mm and 4 mm.

Here a first surface of the raceway element can include a raceway thatinteracts with rolling elements rolling on it. Alternatively the firstsurface of the raceway element can include a sliding surface thatinteracts with another sliding surface, so that the raceway elementsformed as an inner ring or outer ring, or the element serving as theinner ring and the element serving as the outer ring for the bearing, orthe inner ring and the outer ring of the bearing are rotatable againsteach other.

According to a further embodiment, the raceway element is formed bylaser cutting and/or punching from the sheet metal panel. With the aidof laser cutting, arbitrarily shaped raceway elements can bemanufactured without great expense in terms of manufacturing technology.Here the individual dimensions of the raceway elements can be achievedvia a simple software controlling or programming of a control devicecontrolling the laser cutting. An individual manufacturing of punchingtools that are adapted to the respective raceway can thus be omitted.Raceway elements made of plate, in particular metal plate, are therebymore economical even with smaller quantities.

If the raceway element or the plurality of raceway elements are to bemanufactured from a metal plate having a large surface, then a lasercutting device can be relatively easily designed to be movable relativeto the metal plate. In addition, forces acting normal to the plane ofthe metal plate, as is the case with a punching process, that could leadto an undesirable deforming of the edges of the raceway elements, do notarise here. In addition, a particularly precisely shaped edge of theraceway element can be formed by laser cutting, so that, in comparisonto a punched edge, a, for example, machining post-processing step cangenerally be omitted. In this way the manufacturing is simplified. Dueto the laser cutting, the outer contour can be particularly easilyshaped individually so that different shapes for the raceway element canbe manufactured with one and the same tool and from a metal plate of onesize.

According to one preferred embodiment, in a first state o the metalpanel the raceway element has an outer contour in the shape of anessentially rectangular strip, wherein two opposing sides are configuredas joint edges that are connected to each other in a second state inorder to form an annular raceway element. In particular, the essentiallyrectangular strip has two long edges and two short edges, wherein theshort edges are preferably configured as joint edges.

According to a further embodiment, the joint edges are formed bypunching, and the rest of the outer contour, i.e., the two long edges,are formed by laser cutting. Since the joint edges usually have ashorter length in comparison to the rest of the contour of the racewayelement, the negative effects of the punching process can be ignored andtheir positive properties prevail. In addition, a greater heatdevelopment can arise due to the laser cutting, which can lead to ahardening of the edge, which negatively affects a possible later weldingof this edge. By punching of the joint edges that are connected to eachother for the manufacturing of a finished raceway element, in particularwelded, a negative influencing by the possible heat development of thelaser cutting, which can generate the above-mentioned hardenings thatnegatively influence a welding seam, can be prevented.

As mentioned above, according to a further embodiment the one joint edgeof the raceway element is connected via a material-bonded,interference-fit, or friction-fit connection to the other joint edge ofthe raceway element in order to obtain the annular raceway element. Herein particular a material-bonded connection is advantageous, such as, forexample, a welded connection. Here in particular a laser welding ispreferred as opposed to a resistance welding, since the melting materialpushed off during resistance welding can cause protrusions.

According to a further embodiment, the raceway element can alternativelyor additionally include at least one chamfer. The chamfer is preferablyformed along the joint edges. Here the at least one chamfer can receivethe protrusions, such as, for example, upper beads, that arise duringwelding and thus prevent the slipping or rolling of the rolling elementson the raceway element being disturbed.

According to one alternative embodiment, in a first state of the sheetmetal panel the raceway element has an outer contour in the shape of aparallelogram having two sides extending obliquely with respect to acircumferential direction, wherein the two sides extending obliquelywith respect to the circumferential direction are configured as jointedges that are connected to each other in a second state in order toform an annular raceway element.

This has the advantage in particular that the course of the two jointedges connected to each other, i.e., in particular a welding seam,extends obliquely with respect to the circumferential direction of thefinished raceway element, so that in particular in the case of rollingelements that have a line-shaped abutment against the finished racewayelement (rolling elements with linear contact), each can only encountera disturbance at a point, but not over the entire line-shaped abutment,when these rolling elements run over the joint edges connected to eachother. A connecting point for the raceway element can advantageously beprovided, which connecting point minimizes a disturbance of a lineartouching or of a linear contact of a rolling rolling-element, inparticular in comparison to an exclusively radially extending jointedge, by the rolling contact of the rolling element continuouslyoverrunning the connecting point.

In particular, at least one of the joint edges can be configured atleast partially as a first alignment element and/or include at least onefirst alignment element. Here the first joint edge can be alignedradially, axially, and/or circumferentially with respect to the secondjoint edge, whereby it can be achieved that the joint edges to beconnected are aligned precisely flush prior to the connecting process,which can be, for example, a welding process. Consequently the risk canbe precluded or at least significantly reduced that the joint edges areoffset with respect to each other in the connected state. The first andthe second joint edge preferably each include an alignment element. Thealignment accuracy can thereby be increased.

The second joint edge preferably includes a second alignment elementand/or is at least partially configured as a second alignment element,wherein the second alignment element and/or the joint edge at leastpartially configured as a second alignment element is configuredcomplementary to the first alignment element, so that in the connectedstate the first joint edge and the second joint edge are alignedradially, axially, and/or circumferentially with respect to each other.Due to the complementary formation, the joint edges can be automaticallyaligned with respect to each other by engaging one-into-the-other of thealignment elements or of the joint edges configured as alignmentelement.

Furthermore it is advantageous if the alignment element is configuredsuch that a movement of the joint edges with respect to each other inthe axial and/or radial direction is limited or prevented, so that theconnection process can be facilitated and carried out more precisely.For example, the alignment element can include a first and a secondsection that extend by different distances circumferentially, whereby itis prevented that with contacting of the joint edges the first jointedge can be displaced with respect to the second joint edge. The risk isthereby practically precluded that the joint edges are not aligned flushduring welding.

Here the alignment element can additionally serve to configure thecourse of the joint edges connected to each other such that a rollingelement having linear contact does not roll over the connecting jointedges along their entire linear contact, but rather only at partialpoints.

Thus, for example, the first joint edge can include a projectionprotruding in the circumferential direction, and the second joint edgecan include an opening complementary to the protruding projection. Thefirst joint edge can also include a projection protruding in thecircumferential direction and an opening recessed in the circumferentialdirection, and the second joint edge can include an openingcomplementary to the protruding projection and a projectioncomplementary to the recessed opening. It is also conceivable that thefirst joint edge includes a plurality of alignment elements, and thesecond joint edge includes a plurality of complementary alignmentelements corresponding to the plurality of alignment elements. Theprojection and the opening preferably have a triangular shape or asemicircular shape, or the first and second joint edge overall have awave shape. All shapes serve both for aligning and for minimizing thecontact with the over-rolling rolling element.

A further problem in the manufacturing of a raceway element from a sheetmetal panel can occur during the round bending of the strip shapedraceway element, since in particular in the case of greater materialthicknesses the rigidity of the sheet metal panel can impede the roundbending. According to a further embodiment, the raceway elementtherefore includes a bending facilitating recess, for example, in theform of a knurling or ribbing, in order to facilitate a bending of theraceway element into ring shape. Here the bending facilitating recesscan be provided on one of the surfaces that lies opposite the futureraceway of the rolling elements. Alternatively or additionally one edgecan also include such a bending facilitating recess. Here in particularthe at least one bending facilitating recess can extend perpendicular tothe circumferential direction or perpendicular to a longitudinal edge ofthe raceway element. The at least one bending facilitating recesspreferably extends continuously over an entire axial length of thefinished, i.e., annular raceway element, but extends through the totalthickness of the raceway element. A plurality of bending facilitatingrecesses are preferably uniformly distributed over an entirecircumference of the finished, annular raceway element.

According to a further embodiment, an outer contour of the racewayelement includes at least one micro-connection point by which theraceway element is connected during its manufacturing, i.e., inparticular during the punching of the joint edges, to the sheet metalpanel from which the raceway element is manufactured. The at least onemicro-connection point is preferably generated during the laser cutting,for example, by the laser beam briefly being interrupted so that an edgeis not completely laser-cut and a micro-connection point remains. The atleast one micro-connection point can in particular make possible that aplurality of raceway elements are simultaneously formed from the sheetmetal panel, but still in the compound structure of the sheet metalpanel are subjected to a surface processing, such as, for example, ahardening, annealing, or the like, and/or a profiling, as describedbelow. In particular, the manufacturing of the raceway elements canthereby be designed more efficient.

According to a further embodiment, a surface of the raceway element isprovided with a profile, in particular for rolling elements. The profilecan preferably be concave, convex, or straight. In particular, theprofile can be applied onto the surface before the raceway element isround-bent in order to form the finished raceway element. The profilingin particular of the raceway can thereby be simplified. For example, theprofile can already be provided in the sheet metal panel before theraceway element is released by laser cutting and/or punching. It is alsoconceivable that the raceway element is provided with the profile afterits outer contour is formed by laser cutting and/or punching, but theraceway element is still connected to the sheet metal panel via themicro-connection points. This can in particular make it possible toprovide a plurality of raceway elements with a profile in parallel. Itis also possible to provide the raceway element with a profile onlyafter the releasing of the micro-connection points.

For the case that the raceway element is configured as a raceway forrolling elements in a rolling-element bearing including an inner ring,an outer ring, and the plurality of rolling elements that are disposedbetween the inner ring and the outer ring, a flange for the rollingelements can be formed from the same sheet metal panel, wherein theflange is formed one-piece with the raceway element. In particular aconnecting of a flange, which is manufactured separately from theraceway element, can thereby be omitted, whereby a complex orienting andconnecting of the flange to the raceway element can be omitted. Afurther flange can be provided on a side that lies opposite the side onwhich the flange is formed.

The flange is preferably formed by bending. It can be advantageous herewhen at least one target bending point is formed on at least one surfaceof the raceway element in order to facilitate the bending. For example,the target bending point can be configured as a notch. However, otherforms for the target bending point are also possible.

Furthermore, a region of the raceway element that forms the flange canbe rolled and/or milled so that a cross-section of this region isflatter than a cross-section of the rest of the raceway element. Abending of the raceway element in order to form the flange can therebybe simplified.

Since problems can arise during the round bending of the raceway elementdue to the compressing or stretching of the flange necessary therefor,depending on whether the raceway element is used on an inner ring or onan outer ring, the above-mentioned bending facilitating recess canadditionally or alternatively also be formed on an outer edge of theflange in order to facilitate a bending into the ring shape. Inparticular, a plurality of bending facilitating recesses, preferably inthe form of a ribbing or knurling, can be provided that are uniformlydistributed circumferentially around the outer edge of the flange.

Furthermore, at least one recess, in particular a continuous recess, canbe formed in the surface of the raceway element, which surface is formedas a raceway. Here the at least one recess can be configured as alubricant reservoir in order to, for example, improve the lubricationconditions for the rolling elements. Furthermore, the at least onerecess also makes it possible to reduce material, which can on the onehand reduce the costs of the raceway element, and on the other handreduces the weight of the raceway element.

The at least one recess is preferably formed in the region of theconnected joint edges. Furthermore, the first and second joint edge caneach include a first section and a second section, wherein the firstsection and the second section are defined by the recess, and wherein ina state wherein the first and second joint edge are connected to eachother in order to form the annular raceway element, the first sectionand the second section are disposed circumferentially offset withrespect to each other. A welding seam length can thereby be reduced,which in turn reduces the time that is required for generating thewelding seam, and reduces the costs for the welding seam, both withrespect to the working time required and with respect to the weldingmaterial required. Furthermore, the heat introduced into the racewayelement during the welding can be reduced by a shorter welding seam. Afurther advantage is that during the over-rolling of the connected jointedges by a rolling element, the contact with the rolling element isminimized.

For example, the at least one recess can have an essentially elongatedshape whose longitudinal direction extends obliquely with respect to acircumferential direction of the raceway element. Furthermore, the atleast one recess can be disposed along the circumferential direction atan edge region of the raceway element. This makes possible a materialsavings, which can be undertaken in particular on a part of the racewaythat supports no loads, such as is the case, for example, with a balanceshaft.

According to a further aspect, a bearing is provided including at leastone raceway element described above. Here the bearing can preferably bea rolling-element bearing. The rolling-element bearing canadvantageously comprise two of the raceway elements described. Forexample, an inner ring and/or an outer ring of the bearing can includethe raceway element or be formed from the raceway element. The racewayelement can also be attached to the inner ring and/or the outer ring. Ofcourse, a bearing or rolling-element bearing can also be used, whereinan element, for example, a shaft, a hollow shaft, or the like, serves asinner ring, or an element, for example, a housing, serves as outer ring.For example, the bearing can be a ball bearing, a cylindrical rollerbearing, a tapered roller bearing, or the like.

According to a further aspect, a method is proposed for manufacturing araceway element described above, wherein the method includes the steps:

-   -   providing a sheet metal panel, and    -   forming one or more raceway elements from the sheet metal panel.

Here in particular the raceway element is formed by laser cutting and/orpunching. A plurality of elements are preferably formed simultaneously,whereby the manufacturing of the raceway elements can be more efficient,which consequently reduces the manufacturing costs of each individualraceway element, so that even small quantities can be cost-effective.

Furthermore, the method for manufacturing the raceway element caninclude further steps. For example, the method can comprise one or moreof the following steps:

-   -   forming at least one recess in a surface with at least one of        the plurality of raceway elements, which surface is configured        as a raceway,    -   applying a profile onto the raceway element, wherein the profile        in particular is concave, convex, or straight,    -   folding/bending a flange for the rolling elements from the same        sheet metal panel, wherein the flange is formed one-piece with        the raceway element,    -   releasing the raceway element from the rest of the sheet metal        panel by breaking of micro-connection points, via which the        raceway element is connected to the rest of the sheet metal        panel after forming of the raceway elements, provided the        raceway element is attached to the sheet metal panel by the        micro-connection points described above, wherein—when        necessary—a partial releasing of the micro-connection points is        first effected, so that the flange can be formed and        subsequently the micro-connection points that connect the        raceway element to the rest of the sheet metal panel are        released after the forming of the flange, so that during the        folding/forming of the flange the raceway element is still        connected to the sheet metal panel via at least a part of the        micro-connection points,    -   round bending the raceway element,    -   material, friction-fit, and/or interference-fit connecting the        joint edges.

If a plurality of raceway elements are formed from a sheet metal panel,it can be advantageous in particular to arrange the raceway elements onthe sheet metal panel such that the excess material of the sheet metalpanel that is not used for a raceway element is minimized. For thispurpose, for example, the respective outer contours of the plurality ofraceway elements can be arranged on the sheet metal panel such that aregion of the outer contour that forms the at least one recess in theround-bent state of the raceway element receives a region that, in theround-bent state of the raceway element, forms a non-recessed region ofthe raceway element.

Another aspect of the disclosure involves a method comprising forming atleast one pair of parallel laser cuts in a sheet metal panel, each ofthe laser cuts having a first end and a second end, a distance betweenthe pair of laser cuts being less than a length of the laser cuts, thelaser cuts including at least one interruption to create at least onemicro-connection between the first ends and the second ends. The methodalso comprises punching a pair of openings in the sheet metal panel,where the punched openings connect the first ends of the laser cuts andthe second ends of the laser cuts.

Further advantages and advantageous embodiments are specified in thedescription, the drawings, and the claims. Here in particular thecombinations of features specified in the description and in thedrawings are purely exemplary, so that the features can also be presentindividually or combined in other ways.

In the following the disclosure is described in more detail using theexemplary embodiments depicted in the drawings. Here the exemplaryembodiments and the combinations shown in the exemplary embodiments arepurely exemplary and are not intended to define the scope of theinvention. This scope is defined solely by the pending claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depiction of a sheet metal panel including aplurality of raceway elements according to a first exemplary embodimentof the disclosure.

FIG. 2A is a schematic detail view of a round-bent raceway element.

FIG. 2B is a schematic detail view of a round-bent raceway element,wherein the joint edges are connected to each other.

FIG. 3 is a further exemplary embodiment of a raceway element.

FIG. 4A is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 4B is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 4C is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 5A is a raceway element according to a further exemplaryembodiment.

FIG. 5B is a raceway element according to a further exemplaryembodiment.

FIG. 5C is a raceway element according to a further exemplaryembodiment.

FIG. 5D is a raceway element according to a further exemplaryembodiment.

FIG. 6A is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 6B is a cross-section of a raceway element according to a furtherexemplary embodiment.

FIG. 7A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 7B is a plan view of the raceway element according to FIG. 7A in asecond state.

FIG. 7C is a perspective view of the raceway element from FIG. 7B.

FIG. 8A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 8B is a plan view of the raceway element according to FIG. 8A in asecond state.

FIG. 8C is a perspective view of the raceway element from FIG. 8B.

FIG. 9A is a plan view of a raceway element according to a furtherexemplary embodiment in a first state.

FIG. 9B is a plan view of the raceway element according to FIG. 9A in asecond state.

FIG. 9C is a perspective view of the raceway element from FIG. 9B.

FIG. 10 is a schematic process diagram of a method for the manufacturingof a raceway element according to a further exemplary embodiment.

DETAILED DESCRIPTION

In the following, identical or functionally equivalent elements aredesignated by the same reference numbers. The direction designationsused in the following—axial, radial, circumferential—always refer to thefinished raceway element.

FIG. 1 shows a schematic depiction of a sheet metal panel 1 including aplurality of raceway elements 2 according to a first exemplaryembodiment. Each of the raceway elements 1 has an outer contour 4. As isshown in FIG. 1 , a plurality of raceway elements, even differentlydesigned, can be formed from a sheet metal panel 1. Of course, it isalso possible to form only one raceway element 2 from a sheet metalpanel 1.

As is schematically indicated in FIG. 1 by the line thickness, the outercontour 4 of a respective raceway element 2 is formed by laser cuttingand/or punching, wherein the outer contour 4 in the exemplary embodimentshown in FIG. 1 has a rectangular shape.

In particular, a first surface 5 of the raceway element 2 can beconfigured as a raceway that interacts with rolling elements rolling onit. Alternatively the first surface 5 of the raceway element 2 can beconfigured as a sliding surface that interacts with another slidingsurface such that an element serving as inner ring and an elementserving as outer ring for a bearing, or an inner ring and an outer ringof the bearing, are rotatable with respect to each other.

In the exemplary embodiment shown in FIG. 1 , in a first state on thesheet metal panel 1 the raceway element 2 has an outer contour 4 in theshape of an essentially rectangular strip having two long edges 7 andtwo short edges 6. Here the two short edges 6 are configured asso-called joint edges 6-1, 6-2 that are connected to each other in asecond state in order to form the annular raceway element 2. Here theconnecting of the joint edges 6-1, 6-2 can be effected in a material,friction-fit, or interference-fit manner, wherein a material connectionis preferred, in particular by welding.

The joint edges 6-1, 6-2 are preferably formed by punching. Here thispunching of the joint edges 6-1, 6-2 can be effected after the lasercutting of the rest of the outer contour 4, i.e., of the two long edges7. However, punching prior to the laser cutting is preferred since themetal plate still has greater stability here.

The great advantage with combined laser cutting/punching or only withlaser cutting is that, as shown by way of example in FIG. 1 , theraceway element 2 can easily be cut-out from a large-surface sheet metalpanel 1. Here a plurality of raceway elements 2 can be obtained from thesheet metal panel 1, which are dimensioned identically as shown in FIG.1 . However, it is also possible that these raceway elements 2 differ intheir dimensions.

In order to form a spatial fixing of the raceway element 2 or of theraceway elements 2 for steps, for example, occurring after the lasercutting, such as punching, bending, rolling, stamping, and to improvethe manageability of the raceway element 2, the individual racewayelements 2 can preferably each be connected to the rest of the sheetmetal panel 1 via micro-connection points 12 (FIG. 5 ). It can therebyalso be made possible to support the plurality of raceway elementsformed from the sheet metal panel 1 in a flat state, by the racewayelements 2 still remaining connected to the sheet metal panel 1 via themicro-connection points 12. These micro-connection points 12 may bereleased only when the respective raceway element 2 is required. Themicro-connection points 12 are preferably configured such that releasingthe raceway element 2 from the sheet metal panel 1 is possible by asimple manual breaking of the micro-connection points 12. Mechanicaland/or machine breaking or removing is also possible.

In order to also facilitate the storing and handling or the subsequentfurther processing, a plurality of raceway elements 2 can be groupedinto a “Cluster” 14, wherein stabilizing metal-plate regions 16 areformed between the clusters 14. The stabilizing metal-plate regions 16can thus prevent the unintentional release of the raceway elements 2from the sheet metal panel 1. To provide one of the raceway elements 2it can be provided that first the respective cluster 14 is completelyreleased from the rest of the metal plate 1, and in a subsequent stepthe desired raceway element 2 is separated from the rest of the cluster14.

In order to form the finished raceway element 2, it must be brought intoa desired shape (FIG. 2A), for example, by round bending, after it hasbeen cut out from the sheet metal panel 1. The result of such a roundbending is schematically shown in FIG. 2A, wherein for the sake ofsimplicity only a part of the round-bent raceway element 2 is shown.

The two joint edges 6-1, 6-2 can be assembled via a connection, forexample, a welded connection 8 as mentioned above, in order to form thefinished annular raceway element 2. FIG. 2B shows the round-bent racewayelement 2 after the two joint edges 6-1, 6-2 are connected to each otherby the welded connection 8. In order to prevent excess material fromprotruding during connecting, in particular over the surface configuredas raceway 5, as can be seen in the exemplary embodiment depicted ofFIG. 2A or 2B, chamfers 10-1, 10-2, 10-3, 10-4 can be formed along thejoint edges 6-1, 6-2. These chamfers serve for receiving excess materialthat arises during the welding without protrusions of the weldingmaterial impairing the raceway 5.

FIG. 3 shows a further exemplary embodiment of a raceway element 2. Theround bending of the strip-shaped raceway element 2 can be problematicin particular in the case of a sheet metal panel 1 having greatermaterial thickness. Here the round bending of the raceway element 2 canbe facilitated with the aid of bending facilitating recesses 19 that arepresent in the exemplary embodiment depicted in the form of a knurling18. Here the knurling 18 is preferably provided on a side 9 opposite thesurface 5 configured as a raceway. Furthermore, a rolling element 20 isdepicted in FIG. 3 , which rolling element 20 rolls on the raceway 5.

The knurling 18 comprises a plurality of recesses that are distributedcircumferentially over the raceway element 2 and extend perpendicular tothe circumferential direction or perpendicular to a long edge 7 of theraceway element 2. The recesses 19 of the knurling 18 preferably extendcontinuously over an entire axial length of the finished, i.e., annularraceway element 2, but do not extend through the entire thickness 22 ofthe raceway element.

FIGS. 4A, 4B, 4C each show a cross-section through a raceway element 2according to further exemplary embodiments. Depending on theapplication, the raceway element 2 can be provided with a profile forthe raceway 5. FIG. 4A shows a raceway element 2 having a straightraceway profile. FIG. 4B shows a cross-section of a raceway element 2having a crowned or convex profile that is used, for example, in needleroller bearings. In contrast thereto, FIG. 4C shows a cross-section of araceway element 2 having a hollow-shaped or concave profile that isused, for example, with toroidal rollers. The profile can be appliedonto the sheet metal panel 1 prior to the cutting out or final releasingof the raceway element 2.

In order to ensure, for example, that the rolling elements 20 do notcontact along the entire linear contact 21 of the connected joint edges6-1, 6-2 in the case of rolling elements having a linear contact, i.e.,a line-shaped abutment against the raceway 5, such as, for example,needle rollers, cylindrical rollers, tapered rollers, or the like, theconnected joint edges 6-1, 6-2 in the exemplary embodiments that areshown in FIGS. 5A to 5D are disposed obliquely with respect to thelinear contact 21 or obliquely with respect to the long edge 7 of theraceway element, which long edge 7 is parallel to the circumferentialdirection of the annular raceway element 2.

FIG. 5A shows a raceway element 2 in a first state on the sheet metalpanel 1, the one outer contour 4 in the shape of a parallelogram havingtwo short sides 6 extending obliquely with respect to a circumferentialdirection; the short sides 6 are configured as joint edges 6-1, 6-2 thatare connected to each other in a second state in order to form anannular raceway element.

In the raceway elements 2 shown in FIGS. 5B to 5D, the joint edges areadditionally configured as a first or second alignment element 26-1,26-2, using which the first joint edge 6-1 is aligned radially, axially,and/or circumferentially with respect to the second joint edge 6-2, suchthat the joint edges 6-1, 6-2 to be connected are aligned preciselyflush prior to the connection process. As is shown in FIGS. 5B to 5D,the first and the second joint edge 6-1, 6-2 preferably have mutuallycomplementary alignment elements; here the alignment elements 26-1, 26-2in FIG. 5B have a triangular shape, in FIG. 5C a semicircular shape, andin FIG. 5D a wave shape.

As can be seen from the depicted exemplary embodiments, the alignmentelement 26-1, 26-2 can additionally serve to configure the course of thejoint edges connected to each other such that a rolling element 20having linear contact 21 does not roll over the connected joint edges6-1, 6-2 along its entire linear contact 21, but rather only at partialpoints.

For the case that the raceway element 2 forms a raceway 5 for rollingelements 20 in a rolling-element bearing including an inner ring, anouter ring, and the plurality of rolling elements that are disposedbetween the inner ring and the outer ring, a flange 28 for the rollingelements 20 is provided in the exemplary embodiments shown in FIGS. 6Aand 6B, which flange 28 is formed from the same sheet metal panel 1 andis one-piece with the raceway element 2.

The flange 28 is formed by bending, wherein a target bending point 24 isprovided both in the exemplary embodiment in FIG. 6A and in theexemplary embodiment in FIG. 6B. In the exemplary embodiment in FIG. 6B,the target bending point is obtained such that a region 30 of theraceway element 2, which region 30 forms the flange, is rolled and/ormilled such that a cross-section of this region 30 is flatter than across-section of the rest of the raceway element 32. The flange 24 issubsequently formed by folding, turning up, and/or bending of the region30. FIG. 6A shows an alternative target bending point 24 in the form ofa notch.

Since depending on whether the raceway element 2 is used on an innerring or on an outer ring, problems can arise during round bending of theraceway element 2 due to the compression or stretching of the flange 28,a knurling can also be provided on an outer edge 34 of the flange 28 inorder to simplify the bending of the raceway element 2 even with anexisting flange 28.

FIGS. 7 to 9 show exemplary embodiments for a raceway element includingat least one recess 40 that extends continuously through the surface ofthe raceway element 2, which surface is formed as raceway 5. Here FIGS.7A, 8A, and 9A each show the raceway element 2 in a first state beforethe joint edges are connected to each other in order to form the annularraceway element 2. FIGS. 7B, 8B, and 9B show the respective exemplaryembodiment of the annular raceway element 2 in a plan view, and FIGS.7C, 8C, and 9C show the respective exemplary embodiment of the annularraceway element 2 in perspective view.

FIG. 7 shows a raceway element 2 in which the recess 40 is formed as alubricant reservoir in order, for example, to improve the lubricationconditions for the rolling elements 20 and achieve a weight reduction bymaterial saving. Here the recess 40 is formed in the region of theconnected joint edges 6-1, 6-2, wherein the first and second joint edge6-1, 6-2 each include a first section 42 and a second section 44. Thefirst section 42 and the second section 44 are defined by the recess 40and are configured such that in the annular state of the raceway element2 (FIGS. 7B, 7C), the first section 42 and the second section 44 aredisposed circumferentially offset with respect to each other.

Furthermore, the at least one recess also makes it possible to reducematerial, which can on the one hand reduce the costs of the racewayelement, and on the other hand reduces the weight of the racewayelement.

FIG. 8 shows a raceway element 2, wherein the recess 40 is disposed onan edge region of the raceway element 2 along the circumferentialdirection, whereby, for example, a material saving can be achieved in apart of the raceway 5 that supports no loads, such as, for example, witha balance shaft. Furthermore, FIG. 8 in turn shows an oblique course ofthe connected joint edge 6-1, 6-2, which minimizes the contact betweenrolling elements having linear contact and joint edges 6-1, 6-2.

Similar to FIG. 7 , FIG. 9 shows a raceway element 2, wherein the recess40 is formed in the region of the connected joint edges 6-1, 6-2 anddefines a first section 42 and a second section 44 of the first andsecond joint edge 6-1, 6-2, wherein in the annular state of the racewayelement 2 (FIGS. 9B, 9C) the first and second section 42, 44 aredisposed circumferentially offset with respect to each other.

Also in the exemplary embodiments shown in FIG. 7 and FIG. 9 , inaddition to minimizing the length of the joint edges, an obliquepositioning of the joint edges can also be provided in order to furtherreduce the contact between rolling elements having linear contact andconnected joint edges.

FIG. 10 shows a schematic diagram of a method 100 for manufacturing araceway element 2 described above. Here the method comprises a step S1,in which a sheet metal panel 1 is provided. Subsequently in a step S2,one or more raceway elements 2 are formed from the sheet metal panel 1by laser cutting and/or punching. A plurality of elements 2 arepreferably formed simultaneously, whereby the manufacturing of theraceway elements 2 can be more efficient, which consequently reduces themanufacturing costs of each individual raceway element 2, so that evensmall quantities can be cost-effective.

Depending on the raceway element 2 required, the method 100 can includea step S3, in which at least one recess 40 is formed in a surfaceconfigured as raceway 5. Furthermore, in a step S4 a profile can beapplied onto the raceway element 2, wherein the profile is in particularconcave, convex, or straight. Provided the raceway element 2 is stillconnected to the sheet metal panel 1 by micro-connection points 12, in astep S5 these micro-connection points 12 can be released by breaking.However, step S5 can also take place at another point during the method.

Furthermore, the method 100 can include a step S6, in which a flange 28for the rolling elements is formed from the same sheet metal panel, andone-piece with the raceway element, by folding or bending. In order tofinally complete the raceway element 2, in a step S7 the raceway element2 is formed by round bending, and completed in a step S8 by connectingof the joint edges 6-1, 6-2.

In summary a raceway element can be manufactured particularlyeconomically by the raceway element being formed by laser cutting and/orpunching, whereby an individual manufacturing is possible without toolsthat are specifically matched to the dimensions of the raceway element.The raceway element can advantageously be manufactured from a metalplate, wherein during manufacturing the raceway element is stillconnected to the rest of the metal plate via micro-connection points.

Representative, non-limiting examples of the present invention weredescribed above in detail with reference to the attached drawings. Thisdetailed description is merely intended to teach a person of skill inthe art further details for practicing preferred aspects of the presentteachings and is not intended to limit the scope of the invention.Furthermore, each of the additional features and teachings disclosedabove may be utilized separately or in conjunction with other featuresand teachings to provide improved raceway elements.

Moreover, combinations of features and steps disclosed in the abovedetailed description may not be necessary to practice the invention inthe broadest sense, and are instead taught merely to particularlydescribe representative examples of the invention. Furthermore, variousfeatures of the above-described representative examples, as well as thevarious independent and dependent claims below, may be combined in waysthat are not specifically and explicitly enumerated in order to provideadditional useful embodiments of the present teachings.

All features disclosed in the description and/or the claims are intendedto be disclosed separately and independently from each other for thepurpose of original written disclosure, as well as for the purpose ofrestricting the claimed subject matter, independent of the compositionsof the features in the embodiments and/or the claims. In addition, allvalue ranges or indications of groups of entities are intended todisclose every possible intermediate value or intermediate entity forthe purpose of original written disclosure, as well as for the purposeof restricting the claimed subject matter.

REFERENCE NUMBER LIST

-   1 Sheet metal panel-   2 Raceway element-   3 Outer contour-   4 Surface-   6-1, 6-2 Joint edge-   7 Long edge-   8 Connection-   9 Surface-   10-1-10-4 Chamfer-   12 Micro-connection point-   14 Cluster-   16 Metal-plate regions-   18 Knurling-   19 Bending facilitating recess-   20 Rolling element-   21 Linear contact-   22 Thickness-   24 Target bending point-   26-1, 26-2 Alignment element-   28 Flange-   30, 32 Region-   34 Edge-   40 Recess-   42 First section-   44 Second section-   100 Method-   S1-S8 Method steps

We claim:
 1. A raceway element for a bearing, wherein the raceway element is configured as an inner ring or as an outer ring of the bearing, or is configured to be attachable to an element serving as an inner ring or as an outer ring for the bearing, or to an inner ring or an outer ring of the bearing, wherein the raceway element comprises a strip having a substantially parallelogrammatic outer contour with two long sides connected by two short sides, wherein the two long sides and the two short sides are laser cut and/or punched from a sheet metal panel, and wherein the two short sides are joint edges configured to be connected to each other to form an annular raceway element.
 2. The raceway element according to claim 1, wherein the two short sides are not perpendicular to the two long sides.
 3. The raceway element according to claim 1, wherein the two short sides are connected via a material-bonded, interference-fit, or friction-fit connection.
 4. The raceway element according to claim 1, wherein a surface of the raceway element has a profile in an axial direction that is concave or convex.
 5. The raceway element according to claim 1, wherein the raceway element includes at least one bending facilitating recess for facilitating a bending of the raceway element into a ring shape, wherein the at least one bending facilitating recess is provided on a surface opposite a surface of the raceway element that is configured as raceway.
 6. The raceway element according to claim 1, wherein the raceway element includes at least one chamfer formed along the joint edges.
 7. The raceway element according to claim 1, wherein an outer contour of the raceway element includes at least one micro-connection point by which the raceway element is connected to the sheet metal panel from which the raceway element is manufactured.
 8. A rolling-element bearing including at least one raceway element according to claim
 1. 9. The raceway element according to claim 1, wherein the two short sides are perpendicular to the two long sides.
 10. A method comprising: providing a sheet metal panel, forming one or more raceway elements from the sheet metal panel, the one or more raceway elements each having two parallel first sides having a first length and two second sides connecting the two parallel first sides, the second sides having a second length less than the first length and round bending the one or more raceway elements into a ring, wherein the first sides and the second sides are formed by laser cutting and/or punching.
 11. The method according to claim 10, further including: applying a profile to the one or more raceway elements.
 12. The method according to claim 10, further including: releasing the one or more raceway elements from the rest of the sheet metal panel by breaking micro-connection points via which the raceway element is connected to the rest of the sheet metal panel.
 13. The method according to claim 10, wherein the first sides are formed by laser cutting and the second sides are formed by punching.
 14. The method according to claim 13, including mounting the ring on a radial inner circumferential surface or on a radially outer circumferential surface to form a raceway, and mounting a plurality of rolling-elements on the raceway.
 15. A method comprising: forming at least one pair of parallel laser cuts in a sheet metal panel, each of the laser cuts having a first end and a second end, a distance between the pair of laser cuts being less than a length of the laser cuts, the laser cuts including at least one interruption to create at least one micro-connection between the first ends and the second ends; and punching a pair of openings in the sheet metal panel, wherein the punched openings connect the first ends of the laser cuts and the second ends of the laser cuts.
 16. The method according to claim 15, wherein the at least one pair of parallel laser cuts comprises a first cluster of the pairs of the laser cuts and a second cluster of the pairs of the laser cuts spaced from the first cluster.
 17. The method according to claim 15, including: breaking the at least one micro-connection to remove one of the sheet metal strips; bending the removed strip and welding the first end of the removed strip to the second end of the removed strip to form a ring, mounting the ring on a radial inner circumferential surface or on a radially outer circumferential surface to form a raceway, and mounting a plurality of rolling-elements on the raceway.
 18. The method according to claim 17, including applying a profile to a surface of each of the sheet metal strips before forming the laser cuts.
 19. The method according to claim 17, wherein the punched openings are linear and the laser cuts are not perpendicular to the punched openings. 